x1,y1,x2,y2 = map(float,input().split())
print(((x1-x2)**2+(y1-y2)**2)**0.5) x1,y1,x2,y2 = map(float,input().split()) x1 map(float,input().split()) map float input().split() ().split () input split y1 x2 y2 print(((x1-x2)**2+(y1-y2)**2)**0.5) print ((x1-x2)**2+(y1-y2)**2)**0.5 (x1-x2)**2+(y1-y2)**2 (x1-x2)**2 x1-x2 x1 x2 2 (y1-y2)**2 y1-y2 y1 y2 2 0.5 y2 = map(float,input().split()) map(float,input().split()) y2 x1,y1,x2,y2 = map(float,input().split()) map(float,input().split()) x1 y1,x2,y2 = map(float,input().split()) map(float,input().split()) y1 x2,y2 = map(float,input().split()) map(float,input().split()) x2
x1,y1,x2,y2 = map(float,input().split())
print(((x1-x2)**2+(y1-y2)**2)**0.5)
